The provision of caller identification to called parties has proven to be very desirable to telephone subscribers. Caller identification is now available for incoming calls when the called party is not actively engaged in a call as well as when the called party is engaged in a call. When the called party of an incoming call is already actively engaged in a call, a call waiting alert, along with caller identification information, is provided to the called party over the voice channel. Many users find the call waiting alert very interruptive, especially since the user may have to remove the handset of the telephone terminal from her ear to view the caller identification information and assess the relative importance of the call. If the call waiting alert is ignored, the alert may repeat for several seconds to further the interruption.
Although the receipt of caller identification while engaged in a call is potentially beneficial, the interruptive nature of such receipt has lead to many users opting not to subscribe to the service. This loss of subscribers results in loss of revenue for service providers. Since most users would like to receive call waiting alerts for certain incoming calls and not for others, there is a need to allow users to control whether call waiting alerts are provided to them based on predefined criteria.